rs193929352

Positions:

• chr11-17387337-A-G

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_000525.4(KCNJ11):​c.755T>C​(p.Val252Ala) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency: Genomes: not found (cov: 33)
• Consequence: KCNJ11 NM_000525.4 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:1 B:1 O:1
• Conservation: PhyloP100: 9.32

Genes affected

KCNJ11 (HGNC:6257): (potassium inwardly rectifying channel subfamily J member 11) Potassium channels are present in most mammalian cells, where they participate in a wide range of physiologic responses. The protein encoded by this gene is an integral membrane protein and inward-rectifier type potassium channel. The encoded protein, which has a greater tendency to allow potassium to flow into a cell rather than out of a cell, is controlled by G-proteins and is found associated with the sulfonylurea receptor SUR. Mutations in this gene are a cause of familial persistent hyperinsulinemic hypoglycemia of infancy (PHHI), an autosomal recessive disorder characterized by unregulated insulin secretion. Defects in this gene may also contribute to autosomal dominant non-insulin-dependent diabetes mellitus type II (NIDDM), transient neonatal diabetes mellitus type 3 (TNDM3), and permanent neonatal diabetes mellitus (PNDM). Multiple alternatively spliced transcript variants that encode different protein isoforms have been described for this gene. [provided by RefSeq, Oct 2009]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.979

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNJ11	NM_000525.4	c.755T>C	p.Val252Ala	missense_variant	1/1	ENST00000339994.5	NP_000516.3
KCNJ11	NM_001166290.2	c.494T>C	p.Val165Ala	missense_variant	2/2		NP_001159762.1
KCNJ11	NM_001377296.1	c.494T>C	p.Val165Ala	missense_variant	3/3		NP_001364225.1
KCNJ11	NM_001377297.1	c.494T>C	p.Val165Ala	missense_variant	2/2		NP_001364226.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KCNJ11	ENST00000339994.5	c.755T>C	p.Val252Ala	missense_variant	1/1	6	NM_000525.4	ENSP00000345708.4

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 68

GnomAD4 genome Cov.: 33

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:1 Benign:1 Other:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 08, 2023

For these reasons, this variant has been classified as Pathogenic. This sequence change replaces valine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 252 of the KCNJ11 protein (p.Val252Ala). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with neonatal onset diabetes mellitus (PMID: 17021801, 22648966, 22815030; Invitae). ClinVar contains an entry for this variant (Variation ID: 21200). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt KCNJ11 protein function. Experimental studies have shown that this missense change affects KCNJ11 function (PMID: 17021801). This variant disrupts the p.Val252 amino acid residue in KCNJ11. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 21056492, 24622368, 32893419). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. -

Transitory neonatal diabetes mellitus Benign:1

Benign, criteria provided, single submitter

research

Clinical Genomics, Uppaluri K&H Personalized Medicine Clinic

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rs193929352 variant of KCNJ11 gene can cause decreased production and secretion of insulin. This can lead to MODY which is responsive to oral sulfonylureas. -

Permanent neonatal diabetes mellitus Other:1

not provided, no classification provided

literature only

GeneReviews

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.67
BayesDel_addAF	Pathogenic	0.52	D
BayesDel_noAF	Pathogenic	0.52
CADD	Uncertain	25
DANN	Uncertain	1.0
Eigen	Pathogenic	0.72
Eigen_PC	Pathogenic	0.73
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Pathogenic	1.0	D;.
M_CAP	Pathogenic	0.39	D
MetaRNN	Pathogenic	0.98	D;D
MetaSVM	Pathogenic	0.97	D
PrimateAI	Uncertain	0.73	T
PROVEAN	Uncertain	-3.5	D;D
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0010	D;D
Vest4		0.92
MutPred		0.91		Gain of sheet (P = 0.0827);.;
MVP		1.0
MPC		1.8
ClinPred		0.99	D
GERP RS		5.4
gMVP		0.83

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs193929352; hg19: chr11-17408884;